Thanks go to Ryan Farber for the fix.
For any other on-prem/hosted customers (or perhaps anyone with custom domains), this Chrome update introduced another issue for us.
Our normal url is www.xyz.net however, some users on Chrome just access ussing xyz.net (since www is the default, it appears our proxy settings don't force a redirect to add the www). Chrome is so strict that we were getting similar symptoms on other activities for these users (in particular the social group create/edit pages.
We ended up adding a redirect rule in our apache config to check for a url of exactly xyz.net and redirect to www.xyz.netThis seems to be improving things for us as well.